Hot-blast-stove appliance.



F. H. N. GERWIG.

HOT BLAST STOVE APPLIANCE.

APPLICATION FILED MAY 15, I915.

1,1755%; Patnted Mar. 14, 1910 wwrmg saa FREDERICK H. 331'. GERW IG,

KOT-BLAST-STOVE APPLIANCE.

Specification of Letters latent.

ll atentoti ii -i Mitt).

To all whom it may concern;

lie it known that l, FREDERICK. H. N Gniuvio, a citizen of the l'lnited Statt resident of Braddock, in the county oi r gheny and Efitate of lenns vl.Vania have invented certain new and useful improve-- ments in l lot-BlasbStove .fipplianccs, or" which thp following is a specification.

My invention relates to appliances used in supplying air and blast furnace to the combustion chambers of hot blast stoves fou -blast furnaces, in heating the .stove 'checl PlWUl'li. In the use of such hot blast stoves, the air blast is heated y pass-- ing the air blast. through the stoves while under a pressure oi? between 1 and 2 atinospheres, the air absorbing heat from the highly heated checker ivorlt in passing through the refractory checker Work otthe stove to the hot blast inain leading to the blast furnace. In heating, the checker work, between the intervals in which the cold air blast is being heated, a mixture of air and. blast furnace gas, at about atmospheric pressure, is burned within the stove coinbustion chamber, the heated products of combustion passing therefrom through the checker work and out t irough the stack and. heating the checker work in its passage therethrough. I

With existing appliances used in he: tin the checkers of hot blast stoves for blas furnaces the volume of air mixed with th burning gases in heating the store is dependent upon the draft of the stove stack, and in inany cases the amount of air is found to be insuliicient.

One object of my invention to provide a hot blast stove appliance of novel coir structicn having, improved means wher the quantity of air supplied to stoves is materially increased.

Another object of my invention is to provide a hot blast stove appliance for supplying a mixture of blast furnace and air to the combustion chamber of a hot blast stove, having novel means whereby the gases used as fuel in heating: hot blast stoves and the air are thoroughly mixed androinmingled, and the volume of air and gas supplied to the stoves inatcrially increased.

A further object. of my invention is to provide a hot blast stove appliance having improved means whereby the volume of air to the combustion ohan'iber of the 'ulatet and controlled.

--ther objects of my invention will it as will be more fully deter and particularly pointed appended claims.

now to the dwiwings forming specification, r'igure l is a side supplied c i oetoine appar scribed out in in operative position relative to the inlet leading to the combustion chamber of the stove. i2 is a plan, partly in section. of the apparatus shown in 1. Fig, is end elevation the apparatus shown in F e. l and 2'.

In the accoing'ianyiug drawii'i the numeral 2 designates a hot blast stove (of the shown) to the gas box (3 located on the ground level at the base of the stove 2.

The gas box is provided with a flanged och on v "i i which is connected by a pipe "is t s end of the. conduit 9 is provided with a flange it) forming the seat. or support tor the, sliding burner pipe 11 which forms p; t appliance. "lhe burner pipe 11 is circular in cross section ias flanges forming a slide on one end on the sup port 10 formed on the up er end oi the conduit $3, The burer 1 e i has an opening 13 in its side Wall a the rear end thereof which in open or gas discharging position with the similar opening ll in the upperend of the conduit 2. ll. shelf or bracket 16 on the upper end of the pipe 9 provides a support for the pipe 11. and also forms a shutter for the opening 13 when the conduit in retracted position, the burner pipe being arranged to move .lcngthu" .1 on the end of the conduit 9 into and out of gas supplying position which latter is shown in lies 1 and Ii. lever 1'? is keyed or otherwise secured on. the shaft 1'8 and connected by a link 19 with the burner pipe lit, and a burner pipe with the ratchet wheel 22 on speed electric motor 30.

operating lever 20 loosely mounted onone air under a slight pressure is supplied to the combustion chamber 3 of the stove to be mixed with the annular stream of blast furnace gases issuing from the burner pipe 11 in burning the gases within the combustion chamber. The rear end of the air conduit 23 is connected by the connected elbows Bl and 25 with the outlet opening 26 of a rotary fan or blower 27. Mounted on brackcts 28. 28, formed integrally on top of the burner pipe 11 is a base plate 29 on one end of which the fan 27 is mounted, and on the other end of the base plate 29 is a variable The armature shaft 31 of this motoris connected by a flexible coupling 32 with. the driving shaft 33 for the blades of the fan 27. The inlet to the tan or blower 27 has a screen 34 therein to prevent dirt or other solids floating in the atmosphere being drawn into the fan when the fan is in operation.

An annular plate 3% loosely mounted on the end of the burner pipe 11 provides means for regulating the volume and shutting off the supply of air induced to flow into the inlet 4 by the action of the gases entering the stove through the burner pipe 11.

From the above description itwill be readily seen that the motor and fan are permanently secured on top of the movable burner pipe 11 so as to move with this pipe I when the pipe is shifted into and out of its operative position shown in the drawings.

Inthe operation of my improved apparatus the burner pipe 11 is shifted by means of the hand lever 20 into position so that its front or forward end projects into the gas inlet at leading into the combustion chamber 3 of the hot blast stove 2. 'When movement of the pipe 11 into. the position shown is started the motor 30 also is started so as to drive the fan or blower 27, and

pressure through the pipe supply air under 23 to the inlet 4. v c

As the burner pipe 1]. moves lengthwise on the shelves or supports. 10v and 16 the ,opening 13 in the pipe 11 begins to register with the opening 14 inthe upper end of theconduit 9 so as to admit gases from the fine 5 and gas box 6 into the annular burner pipe 11.

An, annular stream of gases flows through the gas inlet 4 into the combustion chamber ing to the bustle pipe of the furnace, the

creased on existing 3 of the stove and in passing through the inlet 4 becomes thoroughly mixed with the air entering the combustion chamber from the air conduit 23. The volume of air entering through this conduit will vary with the pressure and both will vary with the speed at which the fan 27 is driven, so that both the volume and pressure of the entering air is readily regulated and controlled by changing the speed of the variable-speed motor 30 which drives the fan 27. The regulated amount of air supplied in this way insures a more complete combustion of the gases burned in the combustion chamber.

When it is desired to utilize the stove to heat the cold blast, the burner pipe 11 is moved backwardly until its forward end is clear of the outer end of the inlet 4 on the stove 2. In moving the pipe 10 backwardly, which is done by means of the handled lever 20, the opening 13 in the side wall of the pipe 11 will be brought into position above the shelf 16 on the conduit 9 and in'this way shut oh? the supply of gases from the gas box 6 to the pipe 11. The motor 30 will then be stopped by throwing a suitable switch on the feed wires connecting the motor with a source of electric current in the usual known manner. The opening 4 is I then closed by means of a suitable head (not shown )and the cold blast inlet and hot blast outlet on the stoves are opened to admit cold blastvand permit thepassage of the hot blast from the stove into the hot blast main lead blast being heated in passing through thestove checker work in the usual manner.

The advantages of my invention, which will be readily appreciated by those skilled in theart, arise from the, self-contained appliance by which air is supplied to the stove for mixingwith the blast furnace gases in burning the gases in regulated quantities and at a regulated pressure. The provision of the motor driven fan on'the burner pipe enables'the volume of air supply to be instoves and avoids-the necessity of increasing-the height of the stove stack to thereby increase the draft as would otherwise be necessary to increase the air supply to the stove combustion chamber. The apparatus is simple, is easily operated, and is easily and cheaply kept in repair. Modifications in the construction and arrangementof the apparatus may be made without departing from my invention as d'e fined in the appended claims.

I claim g v 1. In a hot blast stove the combination with the stove of a sliding burner pipe for supplying air and gas to the stove combustion chamber, said burner pipe having a. central air conduit and an annular gas conduit surrounding the air conduit, means for supplying gas to the annular gas conduit, a

motor driven fan mounted on the burner pipe to move therewith, means connecting the fan outlet and air conduit to supply air under pressure to said burner pipe, and means for moving said burner pipe into and out of osition relative to the combustion chamber of said stove.

2. In a hot blast stove the combination with the stove of a burner pipe for supplying air and gas to the stove combustion chamber, said burner pipe having air and gas conduits therein, a gas supply pipe on which said burner pipe is movably mounted, a motor driven fan mounted on the burner pipe and movable therewith, a pipe connecting the fan outlet and air conduit on said burner pipe for supplying air under pressure to said burner pipe, and means for moving said burner pipe on the gas supply pipe in regulating the gas supply to the gas conduit.

3. In a hot blast stove the combination with the stove of a burner pipe for supplying air and gas to the stove combustion chamber, said burner pipe having a central air conduit and an annular gas conduit surrounding the air conduit. 21 gas supply pipe 4. In a hot blast stove, the combination with the stove of a burner pipe for supplying air and gas to the stove combustion chamber, said burner pipe having separated air and gas conduits therein, a gas supply pipe connected to the gas conduit, :1 fan mounted on the burner pipe, an air pipe connecting the fan outlet and air conduit for supplying air under pressure to said burner pipe and a variable speed motor for driving said fan.

In testimony whereof, I have hereunto set my hand. M

FREDERICK N. GERWIG. Witnesses JAMES S. SCHWEINBERG, FRANK A. POWER. 

